As you may know, at Scarleteen we do not yet endorse suppressing menstruation/continuous birth control -- using a hormonal method of birth control in order to skip withdrawal bleeds/periods -- for women under 18, because there still is yet to be any study done or published with adolescent women to evaluate if it is safe or medically sound for those in that stage of physical development.
There is yet no available data concerning the long term effects of menstrual suppression on a woman's overall health, at any age. I should also mention that no studies have been published yet about the safety or efficacy of suppressing periods with the patch or vaginal ring.
However, there have been published and reviewed studies for women over 18 using oral contraceptives for suppression.
I have been sexually active for about 3 months now. Usually before sex, my partner and I have a few minutes of unprotected sex and then he puts a condom on. My period is now a week late and I'm worried. I already took a test that came out negative but I'm still kinda scared. My friend told me that it's usual for my period to not come when first having sex....